Time is running out for Christmas shoppers across the country as they hit the high streets in a last-minute buying frenzy. One million people were expected to descend on London's West End over Friday and Christmas Eve , spending an estimated £100m.

A spokesman for the New West End Company, which represents 600 retailers in Oxford Street, Regent Street and Bond Street, added that about 70% of the shoppers were believed to be men who had left their gift-buying to the 11th hour.

Belfast's Victoria Square centre, which opened in March 2008, reportedly saw its busiest day ever on Thursday, with shoppers across Northern Ireland splashing out an estimated £50m on Friday and another spree expected on Saturday.

In contrast, ugly scenes broke out at stores across the US as shoppers vied to lay their hands on Nike's new shoe. The release of the company's retro version of a classic Air Jordan model, which cost $180 (£115) a pair, was responsible for disorder outside stores from California to Georgia.

Back in the UK, Manchester's Trafford Centre and Bluewater in Kent were also among the shopping centres expecting a late surge in customers. But with the rush for last-minute Christmas presents well under way in the UK, many sales have already begun with shops offering discounts of up to 60%.

The e-retail association Interactive Media in Retail Group forecast that consumers would spend £186.4m online on Christmas Day, with the Boxing Day spend expected to be almost double that at £367.8m. However, some online customers aiming to avoid the crowds have been complaining they will not receive their presents in time because of huge delays at the depots of one of Britain's largest delivery firms.

Yodel, which delivers for companies including Amazon, Littlewoods and Mothercare, has been accused of having a backlog of up to 750,000 packages.

The company's chief executive, Jonathan Smith, has admitted to making mistakes and said there had been a huge number of online orders made this year. Among those parcels may be copies of Military Wives' single Wherever You Are, which bookmakers say is hotly tipped to beat X Factor winners Little Mix to the 2012 Christmas No 1 on Christmas Day.

As for getting around, delivery trucks have been forced join the queues as millions of people take to the roads for the annual Christmas getaway. The closure of the Hammersmith flyover in west London, which caused huge tailbacks on Friday, remains in place for emergency repairs. But traffic is still likely to be lighter on most major routes on Saturday.

Rail passengers are facing disruptions, however, especially in Glasgow and the west of Scotland where members of the Rail, Maritime and Transport (RMT) union have begun their three-day walk out in a row over career progression. Many lines across the UK are running reduced services going into the evening.

But freezing temperatures should not cause too much disruption at least. Weather forecasters say it will be a mild and breezy night on Christmas Eve. Christmas Day is also expected to be mild and windy with heavy rain across north-west Scotland.